Container opening device



Oct. 20, 1964 v. CLAIR, JR

CONTAINER OPENING DEVICE 3 Sheets-Sheet 1 Filed Sept. 1, 1961 FIG.3

INVENTOR. Verne Clair, Jr.

ATTYORNEY.

V. CLAIR, JR

CONTAINER OPENING DEVICE Oct. 20, 1964 3 Sheets-Sheet 2 Filed Sept. 1,1961 FIG.8

FIGJI FIG.9

IN l/E N TOR.

r- J .W. m C e n a V 2 plll r G F ATTORNEY.

Oct. 20, 1964 v. CLAIR, JR

CONTAINER OPENING DEVICE 3 Sheets-Sheet 3 Filed Sept. 1, 1961 INVENTOR.Verne Clair, Jr.

ATTORNEY.

United States Patent 3,153,492 CQNTAINER OPENING DEVKIE Verne flair, in,New Hartford, N511, assignor to Kelsey- Hayes Company, Detroit, Mich, acorporation of 'Delaware Filed Sept. l, 1961, Ser. No. 136,400 4 Claims.(U. 22054) The present invention relates to container opening devicesand a method of making the same, more particularly to easy openingdevices of'the general type comprising a rip or tearing tagor'detachable member being cold pressure welded to a wall portion of acontainer consisting of cold pressure weldable metal, such as aluminum,by means of an indentation pressure welded joint, to provide astrip-like weakened section or area of said wall portion, in such amanner as to effect severing or rupturing of the container metal alongsaid area and to produce au opening in the container wall, uponforcefully pulling or tearing said tag or member off said wall portion,substantially without the aid of a special con-- tainer opening tool orimplement, such as an opening key, can opene'r'or the like;

There is already described in U.S. Patent No. 2,792,145

a rip tag easy container opener or detachable member of this type whichconsists of cold pressure weldable metal,

such as aluminum, said tag overlying a wall portion of a sealedcontainer also consisting of coldpressure Weldable material and beingsecured thereto by a closed lineat solid phase indentation pressurewelded joint, such as for instance a ring-shaped joint where it isdesired to produce a circular opening in the container wall. Due to thereduced metal thickness or weakened cross-section of the container wallat the weld line or indented area, as well as to the pressure hardeningof the metal at said area, compared with the adjoining non-indentedareas of the container wall, an opening conforming to the configurationor contour of the weld line or indentation will :be torn in thecontainer wall by severing or rupturing of the container metal, uponforcefully pulling or tearing said tag off the container metalsubstantially without requiring a separate opening aid or implement.Such easy container opening devices are especially suitable for use inconnection with aluminum cans or containers used for the storage offoods or other substances, in particular liquid or semi-liquidsubstances, due to the relative softness and high degree of coldweldability of the aluminurn used as container material.

While easy container opening devices of the type according to theaforementioned patent are especially suitable for the production ofrelatively small openings in a container wall, such as for producingpouring or venting holes in a sealed container containing a liquid orsemi-liquid substance, it has furthermore been proposed by U.S. Patent2,946,478 in the'name of the present applicant as joint inventor, toproduce larger openings by combining a cold welded tearing tag ofthetype mentioned with a weakened or scored line or linesof the container wall, in such a manner as to cause the weld indentation of thecontainer wall to smoothly merge into the score indentation, whereby tofirst tear or rupture the container metal along the weld line or contourand thereafter along the scoring indentation, in such a manner as toresult in an opening having an outline or configuration composed of thecombined weld and score indentations of the container wall. In thismanner, it is posf sible for instance to remove the entire top or anyother wall portion of a container" by the aid of a relatively small ripor tearing 'tag or the like detachable member being cold pressure weldedto the container wall.

Recently it has become customary, for economical and other reasons, toemploy aluminum containers made of ice meals or pre-mixed foods, or thelike substances. In the a case of containers of this type, diificultieshave been experienced in controlling the weld and/or scoringindentations in an effort to ensure consistent and uniform results or toavoid leaks and other defects, as Well as to reduce the number ofrejects or defective cold welded joints or scorings of the finishedunits. Besides, in the case of a material thickness of the order ofmagnitudes of a few thousandths of an inch, the construction of theindenting tools or dies for elfecting both the welding and scoringoperations, as well as the frequent die replacement, becomes an everincreasing and vital problem, whereby to render'the techniques andmethods according to the prior patents more and more unsuited orimpractical as the gauge thickness of the container material isdecreased or as the latter assumes the characteristics of flexible metalsheet or foil having a gauge thickness of the order of magnitudementioned hereinabove. i

Accordingly, an important object of the present inventionis theprovision of an improved tearing tag' container opening device of thetype referred to and a novel method or technique for producing the same,by which the foregoing and related difiiculties and drawbackinconnection with metal sheet containers or containers having a wallthickness of the order of and less than about 0.030 inch.

Another object of the invention is the elimination in the production ofeasy container opening devices of the type referred to of any specialwelding and scoring dies or tools subject to rapid wear as well as toother defects and requiring frequent adjustments and replacements.

Yet another object of the invention is the provision of an improved coldwelded type easy container opening device for sealed sheet metalcontainers or the like which is both simple in construction and can beproduced economically and expeditiously; which does not require anyspecial pressure welding tools subject to Wear and other defects andrequiring frequent replacements; which can be readily adapted to varyingtypes or shapes of containers or openings to be produced; and which willensure an effortless tearing or production of an opening in orseparation of a desired wall portion of a sheet metal container or thelike by the average person, substantially without requiring a specialimplement or opening aid and without the danger of injury to the userwhil effecting an opening operation.

The invention, both as to the foregoing and related objects as well asnovel aspects thereof, will be better understood fromthe followingdetailed description, taken in conjunction with the accompanyingdrawings forming part of this specification and in which:

FIG. 1 is a vertical cross-sectional view through a sealed sheet metalcontainer being fitted with a rip tag easy opening device constructed inaccordance with the principles of the invention;

'FIG. 2 is a plan view of the container of FIG. 1;

FIG. 3 is an enlarged partial sectional view illustrating a toolarrangement for the production of a strip-like cold welded tearing tagor member according to the invention, the position of the elements showncorresponding to the assembly prior to the cold welding operation;

FIG. 4 is an enlarged cross-sectional view taken on line 4-4 of FIG. 2and showing the cold welded tear strip or tag impressed in the containerwall;

FIG. 5 is a longitudinal sectional view of the cold welded strip of FIG.4; r

FIG. 6 is a plan view of FIG. 5;

FIG. 7 illustrates a modified easy opening rip tag or tear strip openeraccording to the invention for the separation of the top of acylindrical container;

FIG. 8 shows an arrangement similar to FIG. 7 but for the production ofa modified easy opening tear strip constructed according to theinvention and structurally embodied in the double crimp joint of the topor cover of a container, the parts being shown in the position prior tothe cold welding operation;

FIG. 11 shows the top according to FIG. after the welding of the tearstrip;

FIG. 12 shows the top in the finalposition joined to the container body;

FIG. 13 is a plan piew of the completed container embodying a rip tagopener according to FIG. 12;

FIG. 14 is a diagram showing a tool assembly for producing a combinedtear strip according to the invention and hermetic seal of two containerhalves;

FIG. 15 is a top view of the container made in accordi I ance with FIG.14; and

FIG. 16 is an enlarged cross-section taken on line 1616 of FIG. '1.

Like reference characters denote like parts throughout the differentviews of the drawings.

With the foregoing objects in view, the invention involves generally theprovision of an elongated or stripi like tearing or container openingmember being embedded in a corresponding depression or indentation of acontainer wall so to fit therein closely and being cold pressure weldedto the bottom of said indentation, except for an end portion of saidmember projecting beyond said wall superimposing an elongated impressionmember of cold pressure weldable metal, preferably in the form of a wirebent to the desired shape or configuration, upon a container wallportion also consisting of cold pressure weldable material, aftercleaning the areas of contact of the members to remove the oxide surfacefilm and other contaminating matter, and applying a pressure to thecontacting'members by means of apair of simple flat-surfaced pressuretools or dies, to cause the wire or the like member to become flattenedand impressed into and flush with the surface of the container wall andto be cold pressure welded thereto by means of a single pressureapplication.

The relation between the diameter or cross-sectional dimension of thewire member to-the gauge thickness of the container wall is such as tocreate an adequate interfacial metal flow between the mating andexpanding wire and container metal surfacesconducive to joining bothmembers by a solid phase cold pressure welded bond or joint uponsubstantially completely embedding said wire in the container wall. Inother words, the extent of weakening or scoring of the container metalmay be accurately controlled by the diameter and'other characteristics,such as the degree of hardness relative to the container metal, of thewire or the like member without the use of any special tools or dieshaving indenters difi'icult to produce and to maintain, especially incase of reduced gauge thicknesses of the container material of the orderof magnitude mentioned hereinahove. Another advantage of this techniqueof producing a cold welded tearing tag or strip is the fact that thewire or the like elongated impression member which serves both as anindenting (scoring) 7 tool or die and as a cold welded rip or tearingstrip, may

to serve as a tearing tag, for the rupturing or severing of thecontainer metal along the edges of said indentation by lifting andforcefully pulling said tag and member oif the container wall. Thelinear strip-like depression or indentation of suitable width and depthand the cold welded tearing tag or strip embedded therein may have anydesired shape orconfiguration conforming with the size and outline ofthe opening to be produced in the container wail.

Looked at from a different angle, the improved tearing tag easy openingdevice according to the invention constitutes a kind of filled scoreline or strip having a desired configuration, to provide a weakenedsection of the container wall along the trace or outline of the openingto be produced with the tearing tag or strip being firmly embedded insaid indentation and secured thereto by cold pressure welding. There iseliminated in this manner the problem of aligning a relatively short tagwith a scored section or line, while avoiding undesirable weakening ofthe scored areas by the latter being'reinforced or strengthened by thetear strip proper, in a manner as will become further apparent as thedescription proceeds:

Aside from the aforementioned advantage of a purely structural nature ofthe easy opening device according to the invention, an essential furtheradvantage resides in the ease and reliability of both scoring orweakening the material andwelding the tearing strip to the weakened orscored section of the container wall by means of a simple pressure toolassembly being devoid of any special indenters or projections subject towear or'breakage, or requiring frequent readjustments or replacements.According to the invention, the scoring or weakening of the containerwall along the trace desired to be ruptured by the tearing operation iseffected in a most simple manner by be pre-shaped or bent to any desiredconfiguration for the production of holes or openings in a container ofa corresponding shape or outline. I

In the production of a cold welded tearing strip or opening device ofthe type described, leaving one end of the wire free so as not beflattened and impressed into the container metal provides a tag forlifting and tearing the main cold welded wire portion welded to thecontainer metal in such a manner'as to sever the container materialalong the edges of the impression or indentation and to produce anopening in the container wall, as will be further understood from thefollowing. I

7 Referring more particularly to FIGS. '1 and 2 of the drawings, thenumeral 10 denotes a container made of metalsheet, such as aluminum andcomprising in the example shown a pair of bottom and top halves orportions 11 and 12 provided with meeting flanges 13 and 14,respectively, and being connected to provide a hermetic seal of thecontainer, such as by means of a double-sided cold pressure weldedindentation joint 15 located near the edges of the flanges, as shown inthe drawing. The joint 15, being immaterial as far as the invention isconcerned, may be of any other suitable type, such as in the form of acrimp joint (see FIG. 11), or any other joint or connection known in theart. Impressed into the flange 14 of the container part 12 and along anarea inwardly of the joint 15 is an elongated or strip-like tearingstrip or member 17 being cold pressure welded to the bottom of theimpression or indentation formed in the flange, to provide what has beenreferred to as a filled score line or strip of weakened section 20 beingclosed upon itself and encircling the flange 14 adjacent to the top orcover 12.

In carrying the inventioninto effect, the embedded and cold welded tearstrip 17 is advantageously produced by impressing a wire or the likeelongated member 18 of cold pressure weldable material into the flange14 also consisting of metal capable of cold pressure welding, asillustrated on an enlarged scale in FIG. 3. According to the latter, thesuperposed wire 18 and flange member 14, after cleaning of thecontacting areas by scratch brushing or the like to provide puremetallic or uncontaminated surfaces, are placed between a pair. offlat-surfaced pressure tools, such as in the form of an anvil 22supporting the flange 14 and a movable tool member 23, whereupon anadequate pressure applied to the superposed members as indicated by thearrow P in the drawing causes the wire 18 to become flattened andimpressed into the container or flange metal, as shown in FIG. 4. By theproper design of the wire diameter D in relation to the gauge thicknesst of the flange 14, an adequate andintense interfacial metal flow willbe created between the mating and expanding surface of the wire and theflange metal conducive to effect a solid phase cold pressure welded bondor. joint between the flattened wire or strip 17 and the bottom of theindentation or scored section 20, as indicated by the dashed line a inthe drawing. An end portion of the wire being left unattached andprojecting from the flange 14 serves as a tearing tag preferably byreversely bending the same upon itself, as shown at 18 in FIGS. 1 and 2.As a consequence, lifting and pulling of the tag 18 from the flangeldcauses the flange being severed or ruptured along the edges of theindentation or weakened area resulting from the impression and coldwelding operation, as shown at sections x-x in FIG. 4, in such a manneras to result in the separation or removal of the top or cover portion 12from the container portion 11. This severing operation requires littleor no effort due to the closely controlled weakening or thickness of thedepressed or scored section Ztlreinforced by the tear strip 17, wherebyto allow the opener to be used safely and expeditiously by the averageperson Without any separate aid or opening implement.

While the ratio between the flange thickness t and the diameter D of thewire 18 is not critical in any narrow sense, it will be appreciated thata wire of too small a diameter will result in the lack of an adequateinterfacial metal flow required for cold pressure welding, while toogreat a wire diameter will result in crushing of the flange before anymetal flow at the interfacehas been started. For practical purposes,satisfactory results may be obtained with wires having a diameter fromabout three to ten times the gauge thickness of the container wall formembers having the same degree of hardness, the most favorable relationbeing advantageously determined by a few simple tests or experiments, tosuit existing conditions and requirements. As an example, a wirediameter of about three times the gauge thickness wil result in the wirebeing distorted to a strip having a width about ten times and having athichness of about 0.75 times of the gauge thickness of the containermaterial, to in turn create an adequate interfacial metal flow betweenthe members conducive to cold pressure welding in the manner described.As a consequence, there will be left a thickness d of the impressed orindented area 2% of the flange or container wall equal to about onefourth of the original wall thickness, whereby to ensure safe and easyrupturing of the wall metal along the edges of the indentation or tearstrip, respectively;

In a practical case, a flange or sheet gauge thickness of t=0.0l inchand a wire diameter of D=0.032 inch resulted in a tear strip 17 of awidth w=0.100 inch and 0.0075 inch thickness, leaving a thickness d of0.0025 of the reduced or scored material 20 suflicient for easy andexpeditious tearing or rupturing of the joint in the manner described.

In order to effect a gradual merging of the flattened wire portion 17into the unflattened portion or tag 18, as shown A in FIGS. and 6, thepressure tool 23 may be formed with a suitable curved edge or corner, inthe manner shown at 24 in FIG. 3. It is further understood that in placeof a round Wire as shown in the drawings, the initial cross-section ofthe impressed member may have any suitable shape, such as square,rectangular, etc. Furthermore, the container may have any shape otherthan rectangular and the tearing tag may .be used for purposes otherthan opening of a container and involving the tearor the like member 26is. preferably located as close as I possible to the edge of the top24,as shown at 26 with the ends of the flattened portion meeting orslightly overlapping one another, to result in a complete severing orremoval of the top 24-, and with the unflattened portion being bentradially inwardly and into a circular tearing tag or member 26.

FIG. 8 shows another modification of a tearing tag or strip according tothe invention, wherein a limited number of spaced fractional portions ofthe wire 26 are impressed into and welded to the container wall or top24 by means of a suitably designed pressure tool 23, FIG. 3, havingspaced projections or indenters as will be readily understood. Acccrdingto this modification, a number of holes along the weld lines or contours27 will be torn in the top 24, whereby to render this type of openerespecially suited for use in connection with containers for the storageand dispensing of powdery or granular substances.

While according to the FIG. 7 modification the entire top 24 is removedfrom the container 25, it is furthermore possible to produce an openingof limited size only in the container wall, such as a pouring or ventinghole, especially for the discharge of liquid or semi-liquid sub stancesstored in the container. A construction of an easy opener of this typeis shown by FIG. 9, wherein both nonflattened ends of the wire 28 aretwisted to form a tearing tag 28, while the flattened and impressed wireportion 28' is bent to an oval, circular or the like closed shapeconforming to the opening to be produced in the container wall.

FIGS. 10 to 13 illustrate a further embodiment'of the inventionespecially suited for circular containers having a top or coverconnected to the container body by a double crimp or an equivalent jointincluding an intermediate cylindrical portion parallel to the containerwall, whereby by the provision of an easy opening tag or strip accordingto the invention upon said intermediate portion thertop of the containermay be removed and reused for protecting the contents left afterpartially emptying the container, in the manner described in and furtherunderstood from the following. Referring to FIG. 10, the numeralEtlrepresents a circular container top or cover having a central depressedportion 31, an intermediate ring-shaped portion 32 and an outer orpre-bent rim portion 33. The cover portion 32 is shown positioned upon aflat anvil 34 and a wire ring 35 is in turn placed in contact with theportion 32 after scratchbrushing or otherwise treating the contactingareas to remove the oxide surface film and other contamination. The wire35 is then impressed into and cold welded to the container top by theaid of a suitable flat-surface welding tool member 36, to produce anembedded tear strip 38 in the intermediate portion 32, in the mannerdescribed and shown by FIG. 11. The top 30 together with the embeddedtear strip 38 is then secured to the open end of the container body 4%by a double crimp joint by interlocking the reversely bent edge portion41 of the container with the edge portion 33 of the top 30, in such amanner as to cause the intermediate portion 32 of the top to assume acylindrical shape parallel to the container wall 40, as shown by FIG.12. As a consequence, upon tearing of the strip 38 by the aid of theprojecting wire or tag 35, FIG. 13, the top will be completely separatedfrom the container body along the line yy and may be reapplied forprotecting the contents left in the container.

FIGS. 14 to 16 illustrate yet another modification of the invention,wherein the embedded wire or the like de tachable tearing member servesboth as a hermetic seal- 7 ing means for the container end as a tearstrip or easy opening device asdescribed herein. For'this purpose, aring-shaped wire 35, FIG. 14, is placed between the superposed flanges13 and 14 of the two halves or parts 11 and 12 of a cylindrical orotherwise shaped container, whereby the flanges will be joined by theflattening of the Wire to both members 13 and 14 upon application of asuitable pressure P to the members bynieans of the tools 34 and 36, asshown at 33 in FIG. 16. In order to enable starting of the tearingaction along the weakened edges or sections xx, a separate tab 41 isconnected to the flange 14 overlying the embedded sealing and tearingstrip 38, such as by means of a criss-cross cold pressure welded jointaccording to US. Patent No. 2,894,322, as shown at 42, or by any othersuitable means or method. As a consequence, upon lifting and pullingthetab 41, the flanges 14 and 15 will be severed along the weakenedportions indicated at xx, whereby to result in the separation of thecontainer halves 11 and 12, in a manner readily understood from theforegoing.

In the foregoing, the invention has been described with reference to afew illustrative devices or embodiments.

'Itwill be evident, however, that variations and modifications, as wellas the substitution of equivalent parts or elements for those shown anddescribed, may be made within tthe broader scope and spirit of theinvention as set forth in the appended'claims. The specification anddrawings are accordingly to be regarded in an illustrative rather thanin a restrictive sense.

I claim: I

1. in combination with a sealed container having at least a wall portionconsisting of cold pressure weldable sheet metal; opening meanscomprising La strip-like area of weakened thickness of said wall portionhaving a width equal to a substantial multiple of the gauge. thicknessof said wall portion, to provide an indentation having an outlinecorresponding to the outline of an opening to be produced in saidcontainer, and a flat elongated detachable member of cold pressureweldable metal having top, bottom and side walls forming a cross-sectionsub stantially conforming to the cross-section of said indentation, saidmember arranged in close-fitting engagement with said indentation andhaving its bottom wall connected to the bottom of said indentation by asolid-phase cold pressure welded bond, said member having an end portionbeing unattached to and projecting from said wall portion, to provide apull tab, whereby to cause severing of the container metal along theedges of said indentation by pulling of said tab.

2. In combination with a sealed container having at least a wall portionconsisting of cold pressure weldable metal sheet; opening meanscomprising a weakened striplike area of said wall portion having athickness less than one half of the gauge thickness of said wall portionand a width equal to a substantial multiple of said gauge thickness, toprovide an indentation having an outline corresponding to the outline ofan opening to be produced in said container, and an elongated detachablemember of cold pressure weldable material comprising a main flattenedportion having top, bottom and side walls forming a cross-sectionsubstantially conforming to the crosssection, of said indentation, saidmain portion arranged in close-fitting engagement with said indentationand having its bottom wallconnected to the bottom of said indentation bya solid-phase cold pressure welded bond, and a non-flattened end portionof said member being unattached to said wall portion and graduallymerging into said flattened portion, to provide a pull tab, whereby tocause a severing of the container metal along the edges of saidindentation by pulling of saidtab.

3. In a container opening device as claimed in claim 2, said indentationand member being substantially closed upon-themselves and adjoiningand-following the edge of a container wall, for severing and removingsaid wall by pulling of said tab Y 4. In combination with a sealedcontainer of the type having a container portion provided with a flange,a cover portion consisting of cold pressure weldable material having anouter zone conforming to and overlying said flange, and means forming ahermetic joint between the outer edge portion of said flange and coverportion; opening means for said container, comprising a-strip-like areaof said cover portion located inwardly of said joint and having asubstantially weakened cross-section, to provide an indentationparallel'to the edge of said cover portion, and an elongated detachablemember of'cold pressure weldable material and comprising a mainflattened portion having top, bottom and side walls forming across-section substantially conforming to the cross-section of saidindentation, said main portion arranged in close-fitting engagement withsaid indentation and having its bottom wall connected to the bottom ofsaid indentation by a solid-phase cold pressure welded bond, and an endportion of said member gradually merging into said flattened portion andbeing unattached to said cover portion, to provide a pull tab, wherebyto enable opening of said container by severing of the cover metal alongthe edges of said indentation by pulling of said tab.

References Cited in the file of this patent UNITED STATES PATENTS924,507 Strathmann .Tune 8, 1909 2,354,081 Weder July 18, 1944 2,592,734Pike Apr. 15, 1952 2,707,823 Sowter May 10, 1955 2,763,057 Clair Sept.18, 1956 2,792,145 Sowter May 14, 1957 FOREIGN PATENTS 127,721 GreatBritain June 4, 1919 706,987 France May 26, 1931

1. IN COMBINATION WITH A SEALED CONTAINER HAVING AT LEAST A WALL PORTIONCONSISTING OF COLD PRESSURE WELDABLE SHEET METAL; OPENING MEANSCOMPRISING A STRIP-LIKE AREA OF WEAKENED THICKNESS OF SAID WALL PORTIONHAVING A WIDTH EQUAL TO A SUBSTANTIAL MULTIPLE OF THE GAUGE THICKNESS OFSAID WALL PORTION, TO PROVIDE AN INDENTATION HAVING AN OUTLINECORRESPONDING TO THE OUTLINE OF AN OPENING TO BE PRODUCED IN SAIDCONTAINER, AND A FLAT ELONGATED DETACHABLE MEMBER OF COLD PRESSUREWELDABLE METAL HAVING TOP, BOTTOM AND SIDE WALLS FORMING A CROSS-SECTIONSUBSTANTIALLY CONFORMING TO THE CROSS-SECTION OF SAID INDENTATION, SAIDMEMBER ARRANGED IN CLOSE-FITTING ENGAGEMENT WITH SAID INDENTATION ANDHAVING ITS BOTTOM WALL CONNECTED TO THE BOTTOM OF SAID INDENTATION BY ASOLID-PHASE COLD PRESSURE WELDED BOND, SAID MEMBER HAVING AN END PORTIONBEING UNATTACHED TO AND PROJECTING FROM SAID WALL PORTION, TO PROVIDE APULL TAB, WHEREBY TO CAUSE SEVERING OF THE CONTAINER METAL ALONG THEEDGES OF SAID INDENTATION BY PULLING OF SAID TAB.